''Clionella aglaophanes'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Clavatulidae Clavatulidae is a Taxonomy (biology), taxonomic family (biology), family of sea snails, marine gastropod mollusks in the superfamily Conoidea. The family is not well differentiated morphologically. Clavatulidae was raised, based on cladistic an ...

Description

The shell grows to a length of 7.6 mm. (Original description) The shell is high, narrow, conically cylindrical, with a blunt, flatly rounded

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics) A-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...

, a short conical base, and scarcely any snout. It is hardly angulated, ribbed, contracted in the sinus area, but barely so at the suture. Its colour is grey, with a silvery sheen. The longitudinal

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

shows the whorls crossed from suture to suture by low, sharpish, subangulately projecting, dextrally convex, hardly oblique ribs, which run continuously, but are slightly diminishing in number, up the spire, there being about 15 on the last and 11 on the first regular

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagra ...

. On the base they bend strongly to the right, and die out at the point of the snout. They are parted by hollowed furrows which are rather broader than they. Both ribs and furrows are scratched with very fine, almost microscopic lines of growth, which coincide with the course of the ribs. In the furrows a few of these lines are slightly stronger than the rest. The spiral sculpture shows below the sinus-area a very slight angular projection of the whorls, which is made more marked by a thickening and elevation of the ribs at this point. This is a feature which on the earlier whorls is very distinct, the whole rib being individualised by the central nodule into which it rises. But further on these nodules lose in importance. At the top of each whorl and close to the suture lies a small flattened thread, rising into minute longitudinal nodules at the ribs. Below this and above the angulation is a slight furrow where the scars of the old sinuses occur. In all this part the surface of the shell is covered by minute spiral threads which lower down become stronger. They are parted by minute furrows of about the same breadth as the threads. These are all exquisitely fretted by the longitudinal scratches. The colour of the shell is greyish, polished, with a very beautiful silvery sheen on the whole surface. The

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spire ...

is conically cylindrical. The

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk ...

is small and the apex broad in proportion to the size of the shell. The profile-lines are hardly interrupted by the sutures. The apex consists of 1¼ broad, depressed, and flatly rounded, smooth whorls. The eight whorls increase very slowly. They are short, the last very small, being scarcely at all more tumid than the rest, and having a short conical base. The snout is very short. There is a small constriction round the top of each whorl. The profile-lines are faintly angulated, but are very slightly convex. The fine suture is well marked, being a little impressed and defined by the slight swelling round the top of the inferior whorl. The superior whorl scarcely contracts towards it. The

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is pear-shaped, with a slight angulation at the top and a very short

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water i ...

below. The outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

is evidently thickened, but chipped in the only specimen present. It runs with an almost continuous slightly convex curve from the body to the siphonal canal, where the curve is slightly and shortly flattened. The sinus is very shallow and open. The inner lip is thickened and raised on a small but defined callus. It runs straight across the body to the base of the short, thick

columella Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

, down which it proceeds direct and parallel to the slightly prominent callus-edge on the left. The point of the columella is rounded and blunt, and hardly advances to the end of the snout, the canal-edge being thick and rounded, cut off obliquely upwards, but not at all reverted. This is an extremely peculiar little shell, remarkable in its narrow cylindrical and compact form, its sculpture, and its slight silvery sheen, from which last feature its name is derived.Challenger Expedition, Report on the scientific results of the voyage of H.M.S. Challenger; Zoology v. 15 pt. 41-43, 1886
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Distribution

This marine species occurs off

Puerto Rico ; abbreviated PR), officially the Commonwealth of Puerto Rico, is a Government of Puerto Rico, self-governing Caribbean Geography of Puerto Rico, archipelago and island organized as an Territories of the United States, unincorporated territo ...

, St Thomas and the

Virgin Islands The Virgin Islands () are an archipelago between the Atlantic Ocean, North Atlantic Ocean and northeastern Caribbean Sea, geographically forming part of the Leeward Islands of the Lesser Antilles in the Caribbean, Caribbean islands or West Indie ...

References

{{DEFAULTSORT:Clionella Aglaophanes aglaophanes Gastropods described in 1882